1. Field of the Invention
The present invention relates to mechanical connectors and, more particularly, to a mechanism for connecting the risers to the suspension lines of a parachute, and for connecting the risers to an article to be decelerated by the parachute.
2. Description of the Prior Art
When an article is to be dropped to the ground from an aircraft or otherwise decelerated, a parachute is used to increase the article's drag. The parachute is composed of a canopy, risers, and suspension lines. The canopy comprises the primary means for increasing drag. Suspension lines connect the canopy to risers, and the risers attach the parachute to the article being dropped or decelerated.
A plurality of risers are used to attach the article to the parachute at a number of distinct points in order to simplify the connecting gear and minimize its weight. The former consideration facilitates the release of the article from the parachute and thereby reduces the time required to release it. A quick release reduces the potential for the article to be damaged by being dragged across the ground or to become entangled by risers and suspension lines when the article is dropped into a body of water. The use of a plurality of risers further stabilizes the article during its deceleration or drop by reducing the rotation of the article about an axis perpendicular to its velocity vector.
A multiplicity of suspension lines are used to maximize the deployment, efficiency, and stability of the deployed canopy. There are always more suspension lines than risers. Parachutes have a confluence area where the risers and suspension lines converge and are connected to each other.
Having a singular confluence area is preferable to having each riser connected to several suspension lines because the former arrangement reduces the probability of entanglement upon deployment of the canopy. A confluence area also allows the canopy to maintain a consistent shape when the attached article rotates and unloads one of the risers.
The parachutes of the prior art use risers having loops at their ends formed by each riser doubling back on itself. A confluence area is obtained by weaving or otherwise binding the risers together adjacent the loops, and connecting the suspension lines to the loops. The foregoing is illustrated in prior art FIG. 1, wherein parachute 11 of the prior art is comprised of canopy 13, suspension lines 15, and risers 17 and 19. Article 21 is attached to risers 17 and 19.
Prior art FIG. 2 is an enlarged drawing of confluence area 23 of parachute 11 where risers 17 and 19 converge and are connected to suspension lines 15. Risers 17 and 19 double back on themselves to form loops 25 and 27. The double thicknesses of risers 17 and 19 are woven together. Suspension lines 15 have eyelets 29 attached to their ends. Loops 25 and 27 run through eyelets 29 to connect risers 17 and 19 to suspension lines 15.
Designers of parachutes have long sought to reduce the bulk and complexity of the connection between the risers and suspension lines because such a reduction reduces the probability of a snag during the unfolding and deployment of a packed parachute, and thus increases its reliability. Furthermore, a reduction in bulk would reduce the weight of the parachute and also allow it to be packed into a smaller volume, thus facilitating its handling and storage.